JP2002186500A - Syrup refiner and method for regenerating mixed bed thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a syrup refiner capable of obtaining a treated syrup with low salt concentration and low color value through reducing the leaks of sodium and/or nitrogen compound(s) such as amino acid(s) into a syrup under treatment without increasing the inversion of sucrose. SOLUTION: This syrup refiner works as follows: a syrup is passed through a strongly acidic cation exchange resin column 2, a weakly basic anion exchange resin column or medium-basic anion exchange resin column 4, a strongly basic anion exchange resin column 6, and a mixed bed column 8 of a weakly acidic cation exchange resin and a strongly basic anion exchange resin in this order. In place of the weakly basic anion exchange resin column or medium-basic anion exchange resin column, a mixed bed column of a strongly acidic cation exchange resin and weakly basic anion exchange resin may be used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sugar solution refining apparatus for desalting and decoloring sugar solutions using an ion exchange resin. More specifically, the present invention is excellent in removing nitrogen compounds such as sodium and amino acids. The present invention relates to a sugar liquid refining apparatus particularly preferably used for refining sugar beet juice. The present invention also relates to a method for regenerating the mixed bed layer of the sugar liquid refining apparatus.

[0002]

2. Description of the Related Art When refining sugar beet juice extracted from sugar beet, an ion exchange treatment for the purpose of desalting is performed as a post treatment of a purification process such as carbonation, filtration, softening and decolorization. At present, a chromatographic treatment is sometimes performed as a pretreatment of the desalting treatment. Desalination improves the crystallinity in the crystallization step of the sugar solution treatment, improves the yield of crystalline sugar and reduces energy cost, and improves the quality of crystalline sugar.

[0003] The ion exchange treatment for the purpose of desalting sugar beet juice is performed by (a) a method in which a sugar solution is sequentially contacted with a strongly acidic cation exchange resin and a weakly basic anion exchange resin at a low temperature to desalinate (cold). Desalting method), (b) a method of further desalting the sugar solution treated by the cold desalting method by a reverse method of sequentially contacting a strongly basic anion exchange resin and a weakly acidic cation exchange resin (complete desalination method) ).

[0004] The above-mentioned complete desalination method is widely used industrially. The feature of this system is that a weakly basic anion exchange resin and a weakly acidic cation exchange resin having good regeneration efficiency are used for the anion exchange resin in the cold desalination step and the cation exchange resin in the reverse step, respectively. For the regeneration of the weakly basic anion exchange resin in the cold desalination step, the recovered waste liquid of the strongly basic anion exchange resin in the reverse step is recovered and used. For the regeneration of the weakly acidic cation exchange resin in the reverse step, the cold desalination step is used. Innovative use of recovering and using the regenerated waste liquid of the strongly acidic cation exchange resin has been introduced to reduce running costs.

[0005]

However, even when sugar beet juice is treated by the above-described complete desalting method, some salts and coloring components may remain in the treated sugar solution. Then, the present inventor analyzed salts contained in the processed sugar solution of sugar beet juice by the complete desalting method. as a result,
It was found that mainly nitrogen compounds such as sodium and amino acids leaked into the treated sugar solution.

[0006] Nitrogen compounds such as sodium and amino acids are
It is an ionic component mainly captured by a strongly acidic cation exchange resin. However, in order to improve the capture rate of these ions, if the conventional complete desalination system increases the regeneration rate of the strongly acidic cation exchange resin or prolongs the contact time between the sugar solution and the strongly acidic cation exchange resin, Since the conversion amount (hydrolysis amount) of sucrose increases and the yield of sucrose decreases, the above-mentioned means has not been actually adopted.

[0007] Further, sodium is an ion to be removed by the weakly acidic cation exchange resin in the reverse step,
When the weakly acidic cation exchange resin is used in the treatment of sugar solution with the ratio of the H-form being high, the treated sugar solution becomes acidic. A method is employed in which a part of the sugar solution is treated without being brought into contact with the weakly acidic cation exchange resin. Therefore, it has been difficult to increase the sodium removal rate by the weakly acidic cation exchange resin in the conventional complete desalination system.

The present invention has been made in view of the above-mentioned circumstances, and is a sugar solution refining apparatus for desalting and decolorizing sugar solutions, particularly sugar beet juice, without increasing the conversion amount of sucrose. An object of the present invention is to provide a sugar solution refining apparatus capable of obtaining a treated sugar solution having a low salt concentration and a low color value by reducing the amount of leakage of nitrogen compounds such as sodium and amino acids into the sugar solution.

[0009]

In order to achieve the above object, the present invention provides the following first and second inventions of a sugar solution refining apparatus. (1st invention) Strongly acidic cation exchange resin layer, weakly basic anion exchange resin layer or medium basic anion exchange resin layer,
A sugar liquid refining apparatus comprising: a strongly basic anion exchange resin layer; a mixed bed layer of a weakly acidic cation exchange resin and a strongly basic anion exchange resin; and a sugar liquid is passed through each layer in this order.

(Second Invention) A strongly acidic cation exchange resin layer, a mixed bed layer of a strongly acidic cation exchange resin and a weakly basic anion exchange resin, a strongly basic anion exchange resin layer, a weakly acidic cation exchange resin and a strongly acidic cation exchange resin And a mixed bed layer of a basic anion exchange resin, wherein the sugar solution is passed through each layer in this order.

In this case, in the sugar liquid purifying apparatuses of the first and second inventions, it is desirable that the temperature of the sugar liquid passing through the strongly acidic cation exchange resin layer is 0 to 10 ° C. This is to prevent hydrolysis (conversion) of sucrose.

Further, the sugar liquid refining apparatuses of the first and second inventions can be particularly suitably used for treating sugar beet juice.

Further, the present invention provides a method for regenerating a mixed bed of a sugar liquid refining apparatus described below. In regenerating the ion-exchange resin of the mixed bed layer of the weakly acidic cation exchange resin and the strongly basic anion exchange resin of the sugar liquid purifying apparatus of the first and second inventions, the weakly acidic cation exchange resin and the strongly basic anion exchange resin are used. A method for regenerating a mixed-bed layer of a sugar liquid refining apparatus, comprising contacting an acid regenerant with an alkali regenerant after contacting a strongly basic anion exchange resin. In regenerating the ion-exchange resin of the mixed bed layer of the strongly acidic cation exchange resin and the weakly basic anion exchange resin of the sugar liquid refining apparatus of the second invention, an alkali regenerant is added to the strongly acidic cation exchange resin and the weakly basic anion exchange resin. And then contacting an acid regenerant with a strongly acidic cation exchange resin.

Hereinafter, the present invention will be described in more detail. The feature of the first invention is that a sugar solution is brought into contact with a mixed bed layer of a weakly acidic cation exchange resin and a strongly basic anion exchange resin in a final stage to remove sodium and a dye in the sugar solution at a high removal rate. is there. In particular, the removal of the dye is performed using a strong basic anion exchange resin, but a high dye removal rate cannot be obtained unless the high-purity sugar solution from which ionic impurities have been almost removed does not contact the strong basic anion exchange resin. . In the first invention, in the mixed bed layer of the weakly acidic cation exchange resin and the strongly basic anion exchange resin, the ionic impurities are almost completely removed particularly in the upstream part of the bed, and the ionic impurities are hardly removed particularly in the downstream part of the bed. By contacting the removed high-purity sugar solution with the strongly basic anion exchange resin, the pigment can be removed at a high removal rate.

The mixed bed layer of the weakly acidic cation exchange resin and the strongly basic anion exchange resin can be said to be a multi-stage treatment using the cation exchange resin and the anion exchange resin.
Impurity ions can be removed at a high removal rate. Therefore, even if a cation component such as sodium leaks from the former stage, the cation component can be removed at a high removal rate by the mixed bed layer of the weakly acidic cation exchange resin and the strongly basic anion exchange resin in the final stage. for that reason,
It is no longer necessary to increase the regeneration rate of the strongly acidic cation exchange resin in the former stage, thereby making it possible to reduce the conversion rate of sucrose in the strongly acidic cation exchange resin layer in the former stage and reduce the amount of the acid regenerant used. .

Further, the conventional complete desalination system has a first
Changes to the system of the invention can be made within the scope of system improvement by simply replacing the last weakly acidic cation exchange resin layer of the conventional complete desalination system with a column having the mixed bed layer. Therefore, according to the first invention, it is possible to remarkably improve product quality within the scope of system improvement.

Meanwhile, in a mixed bed layer of a weakly acidic cation exchange resin and a strongly basic anion exchange resin, it is necessary to regenerate a strongly basic anion exchange resin in order to maintain stable treatment performance. The present inventor has found that a method of contacting an acid regenerant with both a weakly acidic cation exchange resin and a strongly basic anion exchange resin is effective as a method for performing regeneration treatment of the strongly basic anion exchange resin in the mixed bed. Was found. In other words, by using an anionic component of an acid regenerant such as hydrochloric acid or sulfuric acid, which is a regenerant for a weakly acidic cation exchange resin, as a regenerative chemical for a strongly basic anion exchange resin, a new regenerating treatment can be performed only for a strongly basic anion exchange resin. It has been found that the use of chemicals is no longer necessary, and that when the above treatment is performed, the regeneration of the strongly basic anion exchange resin is performed in the regeneration step for each cycle, so that the treatment quality is stabilized.

Accordingly, the present invention provides the above method as a method for regenerating an ion exchange resin in a mixed bed layer of a weakly acidic cation exchange resin and a strongly basic anion exchange resin in the sugar liquid refining apparatus of the first invention. This regeneration method can also be applied to the mixed bed layer in the sugar liquid refining device of the second invention. In this case, a part of the nitrogen compound such as an amino acid is captured by the strongly basic anion exchange resin in the mixed bed layer, but the nitrogen compound such as the amino acid is desorbed by the regenerative treatment.

On the other hand, in the first invention, the amount of leakage of sodium into the treated sugar solution is greatly reduced, and the amount of leakage of nitrogen compounds such as amino acids is also reduced to some extent. The measures are not always enough. This is because the method of using the strongly acidic cation exchange resin is the same as the conventional one.

Nitrogen compounds such as amino acids are also captured by a strongly basic anion exchange resin, but are mainly captured by a strongly acidic cation exchange resin, and their selectivity is lower than that of a monovalent metal such as sodium. Leak from the strongly acidic cation exchange resin at the beginning of the leak. This means that nitrogen compounds such as amino acids are trapped in the lower layer (downstream) of the strongly acidic cation exchange resin layer.

Conventionally, to desorb a nitrogen compound such as an amino acid from a strongly acidic cation exchange resin, a method of passing a sodium salt solution such as sodium hydroxide through the entire strongly acidic cation exchange resin layer has generally been used. That is, since a nitrogen compound such as an amino acid is not easily desorbed from a strongly acidic cation exchange resin by an acid regenerant, it is necessary to perform a regenerative treatment for desorbing a nitrogen compound such as an amino acid by passing a sodium salt solution through the strongly acidic cation exchange resin. Without this regeneration treatment, nitrogen compounds such as amino acids remain in the strongly acidic cation exchange resin, and the quality of the treated sugar solution was not stable.
However, after performing the regenerative treatment, it is necessary to use a large amount of the acid regenerant, which increases the running cost. Therefore, the regenerative treatment is performed only once in several cycles.

As a result of intensive studies, the present inventors have found that to efficiently remove nitrogen compounds such as amino acids from sugar solutions,
It has been found that it is effective to sequentially contact the sugar solution with a mixed bed of a strongly acidic cation exchange resin and a strongly acidic cation exchange resin and a weakly basic anion exchange resin to desalinate. Also,
When regenerating the mixed bed, by contacting both the strongly acidic cation exchange resin and the weakly basic anion exchange resin with the alkali regenerant, nitrogen compounds such as amino acids can be efficiently desorbed from the strongly acidic cation exchange resin. Was found.

When the above desalting treatment is performed, even if nitrogen compounds such as amino acids leak from the strongly acidic cation exchange resin layer at the former stage, they can be captured by the strongly acidic cation exchange resin at the subsequent mixed bed. . Although the reason is not clear, nitrogen compounds such as amino acids are mixed in a mixed bed of a strongly acidic cation exchange resin and a weakly basic anion exchange resin, rather than trapping nitrogen compounds such as amino acids in a single bed of a strongly acidic cation exchange resin. It has been found that the trapping of a compound has a higher removal rate of nitrogen compounds such as amino acids.

Accordingly, the present invention provides the sugar liquid refining apparatus of the second invention described above. The second invention is characterized in that a sugar solution is brought into contact with a mixed bed layer of a strongly acidic cation exchange resin and a weakly basic anion exchange resin at a stage subsequent to the strongest cation exchange resin at the forefront stage, and nitrogen such as amino acids in the sugar solution is mixed. It is to remove a compound at a high removal rate. The present invention also provides the above method as a method for regenerating an ion exchange resin in a mixed bed layer of a strongly acidic cation exchange resin and a weakly basic anion exchange resin in the sugar liquid purifying apparatus of the second invention.

In the sugar liquid purifying apparatus of the second invention, the strongly acidic cation exchange resin for capturing nitrogen compounds such as amino acids is mainly the strongly acidic cation exchange resin of the mixed bed layer. When the mixed bed layer is regenerated, the alkali regenerant is passed through both the strongly acidic cation exchange resin and the weakly basic anion exchange resin so that the alkali regenerant is in contact with the resin. Nitrogen compounds such as amino acids captured by the resin are efficiently desorbed.

Therefore, the use of the above-mentioned regeneration method can reduce the running cost as compared with the conventional case where the entire single-bed layer of the strongly acidic cation exchange resin is regenerated, and the regeneration step in each cycle can be reduced. Since the regeneration of the strongly acidic cation exchange resin is performed, the processing quality is stabilized.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a flow chart showing one embodiment of a sugar solution refining apparatus according to the first invention. In FIG.
Reference numeral 2 denotes a single-bed type strongly acidic cation exchange resin tower (SC tower) having a layer of a strongly acidic cation exchange resin (SC) in the tower, and 4 denotes a single bed having a weakly basic anion exchange resin (WA) in the tower. Bed type weak basic anion exchange resin tower (WA tower), 6 is a single-bed strong basic anion exchange resin tower (SA tower) having a layer of strong basic anion exchange resin (SA) in the tower, 8 is a tower Mixed bed column (WC + SA) having a mixed bed layer of a weakly acidic cation exchange resin (WC) and a strongly basic anion exchange resin (SA) inside
Tower). In the sugar liquid refining apparatus of this example, the sugar liquid is passed through each column in the above order.

FIG. 2 is a flow chart showing one embodiment of the sugar liquid refining apparatus according to the second invention. In FIG. 2, 2 is a single-bed strong acid cation exchange resin tower (SC tower), 10 is a mixed-bed tower of a strongly acidic cation exchange resin and a weakly basic anion exchange resin (SC + WA tower), and 6 is a single-bed strong base. Reference numeral 8 denotes a mixed anion exchange resin tower (WC + SA tower) composed of a weakly acidic cation exchange resin and a strongly basic anion exchange resin. In the sugar liquid refining apparatus of this example, the sugar liquid is passed through each column in the above order.

In FIGS. 1 and 2, the anion exchange resin and the cation exchange resin in the mixed bed columns 8 and 10 are shown as if they were separated from each other vertically. It shows the state, and it goes without saying that these resins are used in a mixed state when the sugar solution is passed.

Further, in the sugar liquid purifying apparatus according to the present invention, one ion exchange resin layer may be arranged in one column as in the embodiment shown in FIGS. The ion exchange resin layer may be arranged in one tower. For example, in the embodiment shown in FIG. 1, the same anion exchange resins, WA and SA, which have different strengths, are stacked and filled in one tower such that WA is an upper layer and SA is a lower layer. Or the interior of one tower is divided into upper and lower two chambers by a liquid-permeable partition plate, WA is filled in the upper chamber, SA is filled in the lower chamber, and the sugar solution is flowed downward, that is, SA from the WA layer. It is good also as a structure which passes a liquid through a layer.

In this case, the SC tower 2 and the SC + WA tower 10
Amberlite (registered trademark, the same applies hereinafter) 200CT, IR120B, IR1
24, IR118, Diaion (registered trademark, the same applies hereinafter) SK1B, SK102, PK208, PK212
Amberlite IRC76, IRC50, Diaion WK10, WK20, etc. are used as the weakly acidic cation exchange resin of the WC + SA tower 8, and Amberlite IR is used as the strong basic anion exchange resin of the SA tower 6 and the WC + SA tower 8.
A402BL, IRA400, IRA440B, IRA
404, IRA900, IRA904, IRA411,
IRA410, IRA910, Diaion SA10
A, SA11A, PA306, PA308, SA20,
Amberlite XE58 as a weakly basic anion exchange resin for the WA tower 4 and the SC + WA tower 10 such as PA418
3, IRA67, IRA96SB, Diaion WA1
0, WA20, WA30, etc. can be used.

In the apparatus shown in FIG. 1, the WA column 4 may be replaced with a single-bed intermediate basic anion exchange resin column having a layer of a basic anion exchange resin in the column. The medium basic anion exchange resin is one in which the anion exchange resin particles themselves have both a weakly basic anion exchange group and a strongly basic anion exchange group. Specific examples thereof include Amberlite IRA478RF having about 35% of a strongly basic anion exchange group and about 65% of a weakly basic anion exchange group. In addition, you may mix and use a weak basic anion exchange resin and a medium basic anion exchange resin.

In the apparatus shown in FIGS. 1 and 2, the SC
In the case of performing a regenerative treatment for desorbing nitrogen compounds such as amino acids by passing a sodium salt solution through the strongly acidic cation exchange resin of the tower 2, the nitrogen compounds such as amino acids are located in the lower part (downstream part) of the strongly acidic cation exchange resin layer. S
It is sufficient to pass the sodium salt solution through only the lower part in the C tower 2. For this purpose, a method can be adopted in which a collector is installed at an intermediate position of the resin layer in the SC tower 2, and in the regeneration step, the sodium salt solution is passed through only the portion below the collector before performing backwashing. . In this case, as the sodium salt solution, for example, sodium hydroxide aqueous solution, saline aqueous solution,
Recycle waste liquid of an anion exchange resin can be used.

[0034]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to the following examples. (Example 1) The sugar liquid refining apparatus of the first invention shown in FIG. 1 was constructed. In this case, Amberlite 120B (1.5 L) was used as the strongly acidic cation exchange resin in the SC tower 2, Amberlite XE583 (2.0 L) was used as the weakly basic anion exchange resin in the WA tower 4, and the strong base was used in the SA tower 6. Amberlite IRA402BL as the reactive anion exchange resin
(0.4 L), Amberlite IRC76 (0.2 L), W
Amberlite IRA402BL (0.4 L) was used as a strongly basic anion exchange resin for the C + SA tower 8.

A method for regenerating the sugar liquid refining apparatus of Example 1 will be described. The SC tower 2 was regenerated by backwashing by passing 3.0 L of a 1N aqueous hydrochloric acid solution and then washed with pure water to complete the regeneration step. The WA tower 4 was regenerated by passing 3.0 L of a 1N aqueous solution of sodium hydroxide therethrough after backwashing, and then washed with pure water to complete the regenerating step. The SA tower 6 was regenerated by passing 0.4 L of a 1N aqueous solution of sodium hydroxide after backwashing, and then washed with pure water to complete the regenerating step.

The regeneration of the WC + SA tower 8 was performed as follows. First, the resin layer was developed 150% by backwashing water in an upward flow, and a weakly acidic cation exchange resin was separated into a lower layer and a strongly basic anion exchange resin was separated into an upper layer. Next, from the upper part of the apparatus, 0.8 L of a 1N aqueous hydrochloric acid solution was passed through both resins at a time in a downward flow to regenerate the lower layer weakly acidic cation exchange resin and regenerate the upper layer strongly basic anion exchange resin. (Figure 1
reference). A strongly basic anion exchange resin is inferior in the performance of removing nitrogen compounds such as amino acids as compared with a strongly acidic cation exchange resin, but the removal performance is stabilized by performing a regeneration treatment. Next, after extruding the aqueous hydrochloric acid solution with water, 0.4 L of a 1N aqueous sodium hydroxide solution is passed downward through the strongly basic anion exchange resin in the upper layer from the top of the apparatus,
Water is passed from the lower part of the apparatus to the lower layer weakly acidic cation exchange resin in the upward flow, and the resin regeneration waste liquid and water are discharged from the collector installed on the separation surface of both resins, and the upper layer strong basic anion exchange resin is discharged. Replayed. Next, washing water was passed through the upper layer of the strongly basic anion exchange resin and the lower layer of the weakly acidic cation exchange resin from the upper and lower portions of the apparatus, and the washing water was discharged from the collector to complete the regeneration treatment. Thereafter, the regenerated weakly acidic cation exchange resin and the strongly basic anion exchange resin were mixed to form a mixed bed.

The sugar beet refining apparatus was used to purify beet sugar juice and regenerate the ion exchange resin. In the purification treatment, the liquid was passed through 15 L as one cycle, and a total of
Cycle pumping and regeneration were performed. The liquid passing temperature was 4 ° C. Regeneration of each column was performed by the method described above. Table 1 shows the properties of the raw sugar solution and the properties of the treated sugar solution when 10 L of the raw sugar solution was treated during the fifth cycle.

Example 2 A sugar liquid refining apparatus according to the second invention shown in FIG. 2 was constructed. In this case, as the strongly acidic cation exchange resin of the SC tower 2, Amberlite 120B (1.0
L), Amberlite 120B (0.5 L), SC + WA as a strong acidic cation exchange resin for SC + WA tower 10
Amberlite XE583 (2.0 L) was used as the weakly basic anion exchange resin in the tower 10, and Amberlite IRA402BL was used as the strongly basic anion exchange resin in the SA tower 6.
(0.4 L), Amberlite IRC76 (0.2 L), W
Amberlite IRA402BL (0.4 L) was used as a strongly basic anion exchange resin for the C + SA tower 8.

A method for regenerating the sugar liquid refining apparatus of Example 2 will be described. The SC tower 2 was regenerated by passing 1.5 L of a 1N hydrochloric acid aqueous solution after backwashing and then washed with pure water to complete the regeneration step. The regeneration of the SA tower 6 and the WC + SA tower 8 was performed in the same manner as in the example.

The regeneration of the SC + WA tower 10 was performed as follows. First, the resin layer was developed 150% by backwashing water in an upward flow, and a strongly acidic cation exchange resin was separated into a lower layer and a weakly basic anion exchange resin was separated into an upper layer. Then, from the top of the device,
3.0 L of a 1N aqueous solution of sodium hydroxide was passed through both resins at a time in a downward flow to regenerate the weakly basic anion exchange resin in the upper layer and to remove nitrogen compounds such as amino acids from the strongly acidic cation exchange resin in the lower layer. Desorbed. After extruding the aqueous sodium hydroxide solution with water, 1.0 L of a 1N aqueous hydrochloric acid solution is passed upward through the strongly acidic cation exchange resin in the lower layer from the lower part of the apparatus, and the weakly basic anion exchange resin in the upper layer from the upper part of the apparatus. Through the water in a downward flow, drain the resin regeneration wastewater and water from the collector installed on the separation surface of both resins,
The lower layer strongly acidic cation exchange resin was regenerated. Next, washing water was passed through the upper layer of the weakly basic anion exchange resin and the lower layer of the strongly acidic cation exchange resin from the upper and lower portions of the apparatus, and the washing water was discharged from the collector to complete the regeneration treatment. Thereafter, the regenerated strongly acidic cation exchange resin and the weakly basic anion exchange resin were mixed to form a mixed bed.

The sugar beet refining apparatus was used to purify sugar beet juice and regenerate the ion exchange resin. In the purification treatment, the solution was passed through 15 L as one cycle, and a total of 5 L was passed.
Cycle pumping and regeneration were performed. The liquid passing temperature was 4 ° C. Regeneration of each column was performed by the method described above. Table 1 shows the properties of the raw sugar solution and the properties of the treated sugar solution when 10 L of the raw sugar solution was treated during the fifth cycle.

(Comparative Example) A single-bed strongly acidic cation exchange resin tower (SC tower), a single-bed weakly basic anion exchange resin tower (WA tower), and a single-bed strong basic anion exchange resin tower (S
A column) and a single-bed weakly acidic cation exchange resin (WC column) to constitute a conventional complete desalting system in which a sugar solution is passed through each column in this order. In this case, as the strongly acidic cation exchange resin of the SC tower, Amberlite 120B (1.5
L), Amberlite XE583 (2.0 L) as a weakly basic anion exchange resin for the WA tower, and Amberlite IRA402 as a strongly basic anion exchange resin for the SA tower.
Amberlite IRC76 (0.2 L) was used as a weakly acidic cation exchange resin for the BL (0.4 L) and WC towers.

A method of regenerating the sugar liquid purifying apparatus of the comparative example will be described. The SC tower was backwashed and then regenerated by passing 3.0 L of a 1N hydrochloric acid aqueous solution, followed by washing with pure water to complete the regeneration step. The WA tower was regenerated by passing 3.0 L of a 1N aqueous sodium hydroxide solution after backwashing, followed by washing with pure water to complete the regenerating step. The SA tower was regenerated by passing 0.4 L of a 1N aqueous sodium hydroxide solution after backwashing,
The regeneration process was completed by washing with pure water.

Regeneration of the WC tower was performed as follows. First, after backwashing, regeneration was performed by passing 0.8 L of a 1N hydrochloric acid aqueous solution, followed by washing with pure water. Then, the pH of the treated sugar solution
For adjustment, 0.2 L of a 1N aqueous solution of sodium hydroxide was passed through to make a part of the resin into Na form, and then washed with pure water. Further, air was supplied to and mixed with the resin layer to uniformly disperse the Na-type resin, thereby completing the regeneration step.

The sugar beet refining apparatus was used to purify sugar beet juice. In the purification treatment, the liquid was passed through 15 L as one cycle, and the liquid was passed and regenerated for a total of 5 cycles. The liquid passing temperature was 4 ° C. Regeneration of each column was performed by the method described above. In this case, the regeneration treatment of the strongly acidic cation exchange resin and the strongly basic anion exchange resin was not performed. The properties of the raw sugar solution and 1
Table 1 shows the properties of the treated sugar solution when the 0 L raw sugar solution was treated.

[0046]

[Table 1]

As is clear from the results shown in Table 1, the sugar liquid purifying apparatuses of Examples 1 and 2 remove salts and coloring components as compared with the conventional sugar liquid purifying apparatus of the comparative example. It was confirmed that the performance was excellent and the properties of the treated sugar solution were stable.

In the embodiment, the regeneration treatment of each tower is performed at the same time, but the regeneration treatment of each tower does not always need to be performed at the same time. Further, in the examples, a whole amount of a new regenerant was used for the regeneration of the weakly acidic cation exchange resin and the weakly basic anion exchange resin, but the regeneration waste liquid of the strongly acidic cation exchange resin and the strongly basic anion exchange resin was used for these regenerations. May be used. Further, the liquid passing temperature is the same in each column, but may be different. For example, as in the conventional case, the liquid may be passed through the first two columns at a low temperature of 10 ° C. or lower and the second column may be passed at a higher temperature. Further, the treatment may be performed by increasing the sugar concentration (Bx) of the raw sugar solution to be passed.

[0049]

As described above, according to the sugar solution refining device of the present invention, the amount of leakage of nitrogen compounds such as sodium and amino acids into the treated sugar solution can be reduced without increasing the conversion amount of sucrose. Thus, a processed sugar solution having a low salt concentration and a low color value can be obtained.

[Brief description of the drawings]

FIG. 1 is a flowchart showing one embodiment of a sugar liquid refining device according to the first invention.

FIG. 2 is a flowchart showing one embodiment of a sugar liquid refining device according to the second invention.

[Explanation of symbols]

2 Single bed strong acid cation exchange resin tower 4 Single bed weak base anion exchange resin tower 6 Single bed strong base anion exchange resin tower 8 Mixed bed tower of weak acid cation exchange resin and strong base anion exchange resin 10 Mixed bed column of strongly acidic cation exchange resin and weakly basic anion exchange resin

Claims (6)

[Claims] 1. A strongly acidic cation exchange resin layer, a weakly basic anion exchange resin layer or a medium basic anion exchange resin layer, a strongly basic anion exchange resin layer, a weakly acidic cation exchange resin, and a strongly basic anion exchange resin. A sugar liquid refining apparatus, comprising: a mixed bed layer of resin; and passing a sugar liquid through each layer in this order. 2. A strongly acidic cation exchange resin layer, a mixed bed layer of a strongly acidic cation exchange resin and a weakly basic anion exchange resin, a strongly basic anion exchange resin layer, a weakly acidic cation exchange resin and a strongly basic anion. A sugar liquid refining apparatus, comprising: a mixed bed layer of an exchange resin, wherein the sugar liquid is passed through each layer in this order. 3. The sugar liquid refining apparatus according to claim 1, wherein the temperature of the sugar liquid passing through the strongly acidic cation exchange resin layer is 0 to 10 ° C. 4. The sugar liquid purifying apparatus according to claim 1, wherein the sugar liquid is sugar beet juice. 5. The method for regenerating an ion exchange resin in a mixed bed layer of a weakly acidic cation exchange resin and a strongly basic anion exchange resin in the sugar liquid refining apparatus according to claim 1 or 2, A method for regenerating a mixed-bed layer of a sugar liquid refining device, comprising contacting an acid regenerant with a basic anion exchange resin and then contacting an alkali regenerant with a strongly basic anion exchange resin. 6. A method for regenerating an ion exchange resin in a mixed bed layer of a strongly acidic cation exchange resin and a weakly basic anion exchange resin of the sugar liquid refining apparatus according to claim 2, wherein the strongly acidic cation exchange resin and the weakly basic acid exchange resin are regenerated. A method for regenerating a mixed bed layer of a sugar liquid refining apparatus, comprising contacting an alkali regenerant with an anion exchange resin and then contacting an acid regenerant with a strongly acidic cation exchange resin.